| Abstract : | Recent observations of rotationally supported galaxies have found a strong correlation (with negligible scatter) between the local observed radial acceleration to the local Newtonian radial acceleration computed from the baryonic mass distribution for the galaxies. It has been named as the Radial acceleration relation (RAR) and it suggests a common acceleration scale a_0 below which dynamical mass exceeds the baryonic mass.
We carry out a test of the RAR for galaxy clusters from three different catalogs compiled in literature, as an independent cross-check of two recent analyses, which reached opposite conclusions. The datasets under consideration are 12 clusters from Vikhlinin Chandra, 12 clusters based on XCOP and 10 clusters from Giles Chandra.
We find the scatters obtained for the RAR for all the three samples to be very low (0.09 - 0.14 dex). However, acceleration scale for the cluster samples being about an order of magnitude higher than that estimated for galaxies and the best fit parameters being discrepant by about 5σ, we conclude RAR to be a non-universal and therefore, an emergent effect.
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